Study of transmission characteristics for a long-period grating on plastic optical fibers and its refractive index sensing

Abstract

Purpose

This study aims to analyze the transmission characteristics of a long-period grating (LPG) fabricated on plastic optical fibers (POFs) and its refractive index (RI) sensing.

Design/methodology/approach

The geometric optic method is used to analyze the factors affecting the transmission characteristics of an LPG on POFs. The RI sensing performances of unbent LPGs and U-bent LPGs fabricated on POFs with different diameters are evaluated experimentally.

Findings

This study shows that the transmission loss caused by LPG strongly depends on the structural parameters of LPG and the environmental RI. For the unbent LPG, the highest RI sensitivity of 1,015%/RI unit (RIU) was obtained in the RI range of 1.33–1.45. For the U-bent LPG without cladding, the highest RI sensitivities of 1,007 and 559%/RIU are obtained in the RI ranges of 1.33–1.40 and 1.40–1.45, respectively.

Originality/value

A geometric optic method is used to analyze the transmission characteristics for an LPG on POFs, and the RI sensing of the LPGs are studied experimentally. The results show the LPG has a good RI sensing performances and is with the features of low-cost, simple structure and easy fabrication.

Citation

Xue, P., Zheng, J., Xu, Y., Bao, H. and Zhang, R. (2022), "Study of transmission characteristics for a long-period grating on plastic optical fibers and its refractive index sensing", Sensor Review, Vol. 42 No. 3, pp. 326-331. https://doi.org/10.1108/SR-10-2021-0347